Exothermic expandable compositions

ABSTRACT

An expandable, exothermic gel-forming composition that is predominately useful in the consumer products and medical industries. More particularly, it relates to the use of expandable particulate exothermic gel-forming compositions with efficient and long-lasting heat production for heating surfaces and objects without the need for electricity or combustible fuel.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 62/433,766, filed on Dec. 13, 2016, the contents of which areincorporated into this application by reference in their entirety as ifset forth verbatim.

FIELD

This disclosure relates generally to exothermic compositions that arepredominately useful in the consumer products and medical industries.

BACKGROUND

The ability to produce heat without the use of electricity or burningfuels is desirable in many applications. In the cosmetic industry, heatis desired for the application of various cosmetics to the skin andscalp. In the medical profession, application of heat is important inphysical therapy, orthopedics, wound healing, arthritis treatment, etc.In consumer products, the ability to keep food and other substances hot,as well as to heat them initially, is desired when other means ofheating are not convenient or unavailable.

The utility of exothermic chemical reactions in such applications hasbeen described. For example, the military has used a “flameless heatingdevice” for heating rations in the field since at least 1973. Thesedevices are in the form of a “hot sheet” consisting of a magnesiumanode, a carbon electrode and an electrolyte salt. More recently, themilitary developed a dismounted ration heating device (DRHD) utilizingchemical heating pads composed of magnesium-iron alloy particles trappedin a semi-solid polyethylene matrix (See, e.g., U.S. Pat. No.4,522,190).

Other examples of metal alloy particles to produce heat in the cosmeticindustry have been described for use in conjunction with paper-based“fluff” as the absorptive material. However, such systems haverelatively low energy potential and thus exhibit a short durationexothermic reaction, as well as non-uniform heating.

Accordingly, there is a need for compositions that can be used togenerate heat in a convenient format that is safe, uniform, controllableand long-lasting. Therefore, a need exists to resolve these and otherproblems in the art.

SUMMARY

The following simplified summary is provided in order to provide a basicunderstanding of some aspects of the claimed subject matter. Thissummary is not an extensive overview, and is not intended to identifykey/critical elements or to delineate the scope of the claimed subjectmatter. Its purpose is to present some concepts in a simplified form asa prelude to the more detailed description that is presented later.

In one embodiment, an expandable, exothermic particulate gel-formingcomposition is provided that includes first and second metallic galvanicalloy particles (or at least two different metallic galvanic alloyparticles that are optionally alloyed together). In other embodiments,more than two different metallic galvanic alloy particles can beprovided. A metallic secondary shell comprised of at least onetransitional metal; and a super absorbent polymer; wherein the first andsecond metallic galvanic alloy particles (or each of the two or moredifferent metallic galvanic alloy particles), the metallic secondaryshell, and the super absorbent polymer are blended with each other;wherein the gel-forming composition expands as the gel-formingcomposition is hydrated and generates an exothermic reaction thatproduces heat for a predetermined duration of time when exposed to waterand an electrolyte. The first and second metallic galvanic alloyparticles, the metallic secondary shell, and the super absorbent polymerin some embodiments are blended with each other are brought intoelectrical contact. In some embodiments, a powder mixture is formed fromfirst and second metallic galvanic particles that are blended with thesuper absorbent polymer. The predetermined duration of time can rangefrom several minutes (e.g., 5 minutes) to several hours (e.g., 8 hours)but can be any duration of time desired or needed. The term“pre-determined” used in connection with a duration of time in thisdisclosure can be something that is known or expected based on therespective composition but not determined at each instance ornecessarily known to a user unless specifically defined as such.

The claimed compositions provide gas suppression, for example hydrogengas suppression, or suppression of gases typically generated by theunderlying exothermic reaction such that these gasses do not escape theformed compositions (referring to the reacted, reacting, formed,gel/foam, expanding or expanded, exothermic, etc. composition) or theirescape is suppressed to a significant degree discussed herein. Incertain embodiments, a majority (or percentage described herein) of thegases produced by the exothermic reaction are suppressed and notreleased from the composition during the exothermic reaction.

In some embodiments, activated carbon is used with the composition as anodor absorber. The activated carbon can be present in an amount of about2 to 25% of the composition. Activated carbon can include a combinationof graphite materials, other carbon powders in various particle sizes.

In one embodiment, an expandable exothermic composition can include twoor more different metallic particles, each having a different oxidationpotential. A metallic secondary shell can be included having at leastone transitional metal. A super absorbent polymer can also be included.The first and second metallic galvanic alloy particles, the metallicsecondary shell, and the super absorbent polymer can be blended witheach other (e.g., to a uniform powder mixture) and the gel-formingcomposition can expand as the gel-forming composition is hydrated togenerate an exothermic reaction that produces heat for a predeterminedduration of time when exposed to water and an electrolyte. In certainembodiments, a majority (or percentage described herein) of the gasesproduced by the exothermic reaction are suppressed and not released fromthe composition during the exothermic reaction.

In often included embodiments, an expandable, exothermic composition isprovided comprising: first and second galvanic alloy particles (or atleast two different metallic galvanic alloy particles that areoptionally alloyed together); a super absorbent polymer; and potassiumpermanganate or potassium ferrate; wherein the first and second metallicgalvanic alloy particles (or each of the two or more different metallicgalvanic alloy particles), the potassium permanganate or potassiumferrate, and the super absorbent polymer are blended with each other;wherein the composition expands as the composition is hydrated togenerate an exothermic reaction and produces heat for a predeterminedduration of time when exposed only to water and an electrolyte. Incertain embodiments, the first and second galvanic alloy particlescomprise MgFe and MnO₂. Also frequently, between about 37% to about 93%,or over 93%, of gases produced by the exothermic reaction are suppressedand not released from the composition during the exothermic reaction.

In another embodiment, an expandable, exothermic composition is providedcomprising: manganese oxide blended with a super absorbent polymer; andwherein the composition expands as the gel-forming composition ishydrated to generate an exothermic reaction and produces heat for apredetermined duration of time when exposed only to an aqueous solution.In some embodiments, the manganese oxide is manganese dioxide. Incertain related embodiments, a majority (or percentage described herein)of the gases produced by the exothermic reaction are suppressed and notreleased from the composition during the exothermic reaction.

In some embodiments, the composition expands to form a stiff foam. Insome embodiments, the composition fluffs up as the composition ishydrated. In some embodiments, the aqueous solution is hydrogen peroxideand the buffering agent is a blended mixture of compressed sponge and/orclay particles. In this regard embodiments, the composition of thisembodiment can expand to form a stiff foam. In certain relatedembodiments, a majority (or percentage described herein) of the gasesproduced by the exothermic reaction are suppressed and not released fromthe composition during the exothermic reaction.

Kits are also provided, for example a kit comprising: a container; anexothermic particulate gel-forming composition according to any of thepreceding claims;-an aqueous activator solution, wherein the superabsorbent polymer is operable to absorb the aqueous activator solutionso that the gel-forming composition expands as the gel-formingcomposition is hydrated; and instructions specifying that thecomposition is activated in the absence of air upon contact with theaqueous activator solution to produce heat for a predetermined durationof time.

In another embodiment, an expandable, exothermic particulate gel-formingcomposition is provided comprising: first and second metallic galvanicalloy particles comprising magnesium and iron; a metallic secondaryshell comprised of at least one transitional metal comprising manganesedioxide; and a super absorbent polymer comprising sodium polyacrylamide;wherein the first and second metallic galvanic alloy particles, themetallic secondary shell, and the super absorbent polymer are blendedwith each other; wherein the gel-forming composition expands as thegel-forming composition is hydrated and generates an exothermic reactionthat produces heat for a predetermined duration of time when exposed towater and an electrolyte. In certain related embodiments, a majority (orpercentage described herein) of the gases produced by the exothermicreaction are suppressed and not released from the composition during theexothermic reaction.

In another embodiment, an expandable, exothermic composition is providedhaving first and second metallic galvanic alloy particles comprisingmagnesium and manganese oxide (i.e. whereby the galvanic alloy particlesdo not include iron). A super absorbent polymer can be included as wellas a carbon particles. The first and second metallic galvanic alloyparticles, the super absorbent polymer, and the carbon can be blendedwith each other. The composition expands as the composition is hydratedwith water and no electrolyte such as salt is necessary for inclusion inthe water. Hydrating the composition can generate an exothermic reactionthat produces heat for a predetermined duration of time. In certainrelated embodiments, a majority (or percentage described herein) of thegases produced by the exothermic reaction are suppressed and notreleased from the composition during the exothermic reaction.

In another embodiment, an expandable, exothermic (particulate)gel-forming composition is provided comprising: first and secondgalvanic alloy particles comprising magnesium and iron; a superabsorbent polymer comprising sodium polyacrylamide; and potassiumpermanganate or potassium ferrate; wherein the first and second metallicgalvanic alloy particles, the potassium permanganate or potassiumferrate, and the super absorbent polymer are blended with each other;wherein the gel-forming composition expands as the gel-formingcomposition is hydrated and produces heat for a predetermined durationof time when exposed only to water and an electrolyte. In certainrelated embodiments, a majority (or percentage described herein) of thegases produced by the exothermic reaction are suppressed and notreleased from the composition during the exothermic reaction.

In another embodiment, an expandable, exothermic composition that isfluffable and/or swellable is provided comprising: manganese oxideblended with a super absorbent polymer comprising sodium polyacrylamide.This embodiment can use a super absorbent polymers disclosed herein thatare not sodium polyacrylamide. The composition expands as thecomposition is hydrated and produces heat for a predetermined durationof time when exposed only to an aqueous solution. In certain relatedembodiments, a majority (or percentage described herein) of the gasesproduced by the exothermic reaction are suppressed and not released fromthe composition during the exothermic reaction.

In another embodiment a kit is provided comprising: a container; anexothermic particulate gel-forming composition according to any of thepreceding claims; an aqueous activator solution comprising water or asaline solution, wherein the super absorbent polymer is operable toabsorb the aqueous activator solution so that the gel-formingcomposition expands as the gel-forming composition is hydrated; andinstructions specifying that the composition is activated in the absenceof air upon contact with the aqueous activator solution to produce heatfor a predetermined duration of time.

In frequent embodiments contemplated herein, the composition is adaptedto provide for minimal or approximately zero gases to be produced orreleased from the composition (referring to the reacted, reacting,formed, gel/foam, expanding or expanded, exothermic, etc. composition)during or otherwise as a result of the exothermic reaction. Often,between about 37% to about 93% of gases produced by the exothermicreaction are suppressed and not released from the composition during orotherwise as a result of the exothermic reaction. Also often, betweenabout 93% to about 100% of gases produced by the exothermic reaction aresuppressed and not released from the composition during or otherwise asa result of the exothermic reaction. In frequently included embodiments,over at or about 40%, over at or about 45%, over at or about 50%, overat or about 55%, over at or about 60%, over at or about 65%, over at orabout 70%, over at or about 75%, over at or about 80%, over at or about85%, over at or about 90%, or over at or about 93%, or over at or about95% of gases produced by the exothermic reaction are suppressed and notreleased from the composition (again, referring to the reacted,reacting, formed, gel/foam, expanding or expanded, exothermic, etc.composition) during or otherwise as a result of the exothermic reaction.

Other aspects of the disclosed solution are found throughout thespecification. To the accomplishment of the foregoing and related ends,the aspects disclosed in the specification are indicative, however, ofbut a few of the various ways in which the principles of the claimedsubject matter may be employed and the claimed subject matter isintended to include all such aspects and their equivalents. Otheradvantages and novel features may become apparent from the followingdetailed description.

DETAILED DESCRIPTION

This solution is in the field of expandable, exothermic gel-formingcompositions that are predominately useful in the consumer products andmedical industries. More particularly, the herein disclosed solutionrelates to the use of expandable, particulate exothermic gel-formingcompositions with long-lasting and efficient heat production for heatingsurfaces and objects in the absence of air without the need forelectricity or combustible fuel. The exothermic gel-forming compositionsof the present disclosure are generally formulated from severalapproaches.

Terms with commonly understood meanings may be defined herein forclarity and/or for ready reference, and the inclusion of suchdefinitions herein should not necessarily be construed to represent asubstantial difference over what is generally understood in the art. Allpatents, applications, published applications and other publicationsreferred to herein are incorporated by reference in their entirety. If adefinition set forth in this section is contrary to or otherwiseinconsistent with a definition set forth in the patents, application,published applications and other publications that are hereinincorporated by reference, the definition set forth in this sectionprevails over the definition that is incorporated herein by reference.

As used herein, “a” or “an” means “at least one” or “one or more.”

As used herein, the term “user,” “subject,” “end-user” or the like isnot limited to a specific entity or person. For example, the term “user”may refer to a person who uses the systems and methods described herein,and frequently may be a technician. However, this term is not limited toend users or technicians and thus encompasses a variety of persons whocan use the disclosed systems and methods.

The disclosed solution can now be better understood turning to thefollowing detailed description. It is to be expressly understood thatthe described embodiments are set forth as examples and not by way oflimitations on the embodiments as ultimately defined in the claims.

It is understood that “galvanic alloy” can mean a metal that is made bycombining two or more metallic elements, including combining two or moredifferent metal salts. The combination is often via a known means foralloying, including for example using an alloying process using a ballmill or the like.

It is understood that the term “blended” can mean blending two or morethings together to form a mixture, such as a blended powder (uniformlyor otherwise), homogeneous mixture or homeogenous powder. A blender thatcan be used to “blend” two or more things together can includecommercially available mixers and blenders, such as drum mixers, braunmixers, ribbon blenders, blade blenders, V-shaped blenders, batchmixers, or the like.

It is understood that the term, “activator solution,” can mean water,water and an electrolyte, or other aqueous solution that when contactedwith any of the exothermic compositions of this disclosure initiates,increases or renews an exothermic reaction.

As used herein, the term “gel” is intended to refer to materialstraditionally known in the art as gels, in addition to foams andcombinations thereof. Often, when formed, the foam is a foam having acertain level of structural rigidity or shape adherence such as a stifffoam. Such stiff foam may be capable of withstanding deformation againsta certain level of outside force or be a self-supporting foamcomposition. As such, a gel-forming composition is intended herein torefer to a gel-forming composition and unless specifically indicatedotherwise, also refers to a foam-forming composition. Also for example,an exothermic gel is intended herein to refer to an exothermic gelcomposition and unless specifically indicated otherwise, also refers toan exothermic foam composition. Also for example, a swelling gel or agel matrix also, therefore, is intended to refer herein to a swellingfoam or a foam matrix unless specifically indicated otherwise.

As used herein, an “exothermic composition” may be referred to as an“exothermic composition” prior to, during, or after initiation of anexothermic reaction using the composition.

The use of self-heating compositions is well known. Magnesium-Ironalloys activated by salt and water have been used by the military andrecreational markets for decades. All of these reactions, however, areuncontrollable, violent and short in duration. These reactions use anoxidation-reduction reaction to effectively oxidize the metallicelements by splitting the water molecule into oxygen to produce heatwhile liberating hydrogen gas. This evolution of hydrogen gas can be amajor limiting factor as to where these compositions can be used becauseof the explosive nature of hydrogen gas under normal atmosphericconditions.

Prior approaches to self-heating have incorporated galvanic alloys (e.g.Mg—Fe alloys) in combination with a super absorbent polymer (SAP). Inturn, such approaches have achieved self-swelling gels formed by afluffing action upon contact of the SAP with an aqueous solution (e.g.water or saline solution). This in turn permits the correspondingexothermic gel to expand to contour around objects and fill voids. Moreimportantly, the swellable agents of the SAP electronically interferewith the oxidation process of the Mg—Fe, and with an understanding ofthe hydrogen bonding forces at play within the reaction, a controlledreaction can be designed with a calculated output of heat over a knowntime period. The heat-vs-time buffering effect of the SAP works withinits own structure by utilizing the electron sharing and hydrogen-bondingforces in a tug-of-war between the oxidation tendencies of the galvanicalloy in the presence of water and an electrolyte. More specifically, asalt solution and the electronic attraction forces of the SAP matrix,namely hydrogen bonding and valence sharing. But as applicable as acontrolled, calculated, time-release exothermic reaction powered bywater can be, it still has the disadvantage of evolving hydrogen gas asa byproduct of the reaction.

Galvanic Alloy Particles

As discussed throughout this disclosure, those embodiments of thedisclosed solution that include galvanic alloy (GA) particles canconsist of a mixture of two or more metallic agents, each with adifferent oxidation potential, such that one serves as the cathode andthe other serves as the anode in an electrochemical reaction, once thetwo components of the composition are brought into electrical contactwith one another via an activator solution.

Exemplary metallic agents can include mixtures of copper, nickel,palladium, silver, gold, platinum, carbon, cobalt, aluminum, lithium,iron, iron(II)oxide, iron(III)oxide, magnesium, manganese, Mg₂Ni, MgNi₂,Mg₂Ca, MgCa₂, MgCO₃, MnO₂, and combinations thereof. For example,platinum may be dispersed on carbon and this dispersion used as acathode material. See, e.g., U.S. Pat. Nos. 3,469,085; 4,264,362;4,487,817; and 5,506,069.

An exemplary anode material is magnesium, which reacts with water toform magnesium hydroxide (Mg(OH)2) and hydrogen gas to generate largeamounts of heat. Other metallic agents having high standard oxidationpotentials (such as lithium) may also serve as the anode material, butare less preferred from a cost and safety standpoint. The cathodematerial will have a lower standard oxidation potential than the anodematerial. The cathode is not consumed in the electrochemicalinteraction, but serves as a site for electrons given up by thecorroding anode to neutralize positively charged ions in theelectrolyte. Exemplary cathode materials include iron, copper andcobalt.

In certain exemplary embodiments, the galvanic alloy comprises twodifferent alloys that are alloyed together. Most often, such an alloycomprises a combination of two different galvanic alloys describedand/or contemplated herein. For example, in one embodiment, the galvanicalloy comprises MgFe alloyed with MnO₂.

Any of the usual methods can be employed in the production of a galvanicalloy, such as conventional dissolution or mechanical alloying. Theprocess of mechanical alloying involves, for example, inducing a solidstate reaction between the components of an initial powder mixture byrepeated mechanical deformations caused by ball-powder-ball collisionsusing a high energy ball mill. Such mechanical deformations may include,for example, repeated flattening, fracturing, and welding of metalconstituents e.g., active and passive metal particles. The resultantenergy produced from the impact of colliding steel balls with particlestrapped between them creates atomically clean particle surfaces. Theseatomically clean particle surfaces allow them to cold-weld together.

The particle sizes of the metallic components before milling may varyfrom a few microns to a few hundred microns. In one embodiment, it maybe desirable to have an average particle size less than 200 microns,such as 100-150 microns, to facilitate efficient alloying.

Exposure to oxygen or certain other reactive compounds produces surfacelayers that reduce or completely eliminate the cold welding effect.Therefore, an inert atmosphere can be maintained in the mill to preventreoxidation of the clean surfaces, thereby avoiding the formation ofoxide coatings on the particle surfaces which reduce galvanic cellreactions. An “inert gas” as used herein is an unreactive gas, such asnitrogen, helium, neon, argon, krypton, xenon, radon and also includesthe nonoxidizing gas, carbon dioxide. The inert gas should beessentially free of water (less than 10 ppm, such as less than 5 or lessthan 1 ppm).

Generally, when the milling process is allowed to progress for anextended period of time, the particle structure becomes more refined andthe cathode particles reduce in size. However, after a certain point inthe milling process, any additional milling will result in a reductionof the corrosion rate due to the cathode material becoming too finelydispersed throughout the anode material. When this occurs, the ratio ofcathode/anode particle surface area available for contact with theelectrolyte decreases and hence the corrosion rate decreases. Theresulting mechanically alloyed powders from a milling process are smallparticles consisting of matrices of active metal having smallerparticles of passive metals dispersed throughout. Accordingly, millingtime should be optimized for the best outcome in terms of electricalconductivity. In one embodiment, the galvanic alloy particles consist ofmagnesium and nickel, magnesium and iron, magnesium and copper, andmagnesium and cobalt (U.S. Pat. No. 4,264,362). In magnesium-containingalloys, the magnesium is usually present in greater abundance, such asgreater than 75%, 80%, 90% or 95% by weight.

Super Absorbent Polymer

In those embodiments of the disclosed solution that include asuperabsorbent polymer (SAP), it is understood that SAP can be a “slushpowder,” “water-insoluble absorbent hydro gel-forming polymer,”“hydrogel-forming” polymer or “hydrocolloid.” The use of SAP isimportant because, when combined with an aqueous solution, a gel thatexpands can be created. This water-based gel can store a significantamount of the heat generated by the exothermic reaction due to its highspecific heat capacity. Thus, the gel stays hot for a relatively longperiod of time (compared to the exothermic reaction carried out in theabsence of gel). The gel also prolongs the duration of time that theobject being heated can be maintained at a relatively constant elevatedtemperature. Additionally, as the gel-forming composition expands, heatcan be transferred to more surface area of external objects than if thegel did not expand.

The term “super absorbent polymer” can be any polymer capable ofswelling to 200 gms per gm of dry polymer when exposed to water.Generally, SAPs are loosely cross-linked, three-dimensional networks offlexible polymer chains that carry dissociated, ionic functional groups.The absorption capacity of a SAP relative to a particular material, suchas water, is determined by osmotic pressure and the polymer's affinitywith that material as well as the polymer's rubber elasticity.

The difference between the ion concentration inside a SAP and that ofthe surrounding water solution determines the intensity of availableosmotic pressure. Therefore, the osmotic pressure enables a SAP toabsorb a large quantity of water. Additionally, a particular polymer'saffinity for its surrounding solution also affects the absorptioncapacity of the polymer. Thus, based on a polymer's absorptive capacitydue to the surrounding osmotic pressure and the polymer's affinity forwater, a SAP can absorb large quantities of water and other aqueoussolutions without dissolving by solvation of water molecules viahydrogen bonds, increasing the entropy of the network to make the SAPsswell tremendously.

The factor that suppresses a SAP's absorbing power, in contrast, isfound in the elasticity of the gel resulting from its network structure.The rubber-like elasticity of a polymer increases with the crosslinkingdensity of the polymer, wherein the absorption capacity of a given SAPreaches its maximum when its rubber elasticity attains equilibrium withits water absorbing power.

Examples of SAPs can include a polyacrylic acid salt-based polymer, avinyl alcohol-acrylic acid salt-based polymer, a PVA based polymer or anisobutylene-maleic anhydride polymer. Other examples of SAPs includepolysaccharides such as carboxymethyl starch, carboxymethyl celluloseand hydroxypropyl cellulose; nonionic types such as polyvinyl alcoholand polyvinyl ethers; cationic types such as polyvinyl pyridine,polyvinyl morpholinione, and N,N-dimethylaminoethyl orN,N-diethylaminopropyl acrylates and methacrylates; and carboxy groupswhich include hydrolyzed starch-acrylonitrile graft copolymers,partially neutralized hydrolyzed starch-acrylonitrile graft copolymers,hydrolyzed acrylonitrile or acrylamide copolymers and polyacrylic acids.

Methods of making SAPs are well known and can be easily optimized toachieve a desired swellability. For example, SAPs can be made from thepolymerization of acrylic acid blended with sodium hydroxide in thepresence of an initiator to form a polyacrylic acid sodium salt (i.e.“sodium polyacrylate.) Other materials also used to make SAPs arepolyacrylamide copolymer, ethylene maleic anhydride copolymer,cross-linked carboxy-methyl-cellulose, polyvinyl alcohol copolymers andcross-linked polyethylene oxide.

Although there are many types of SAPs commercially available, most arelightly cross-linked copolymers of acrylate and acrylic acid, andgrafted starch-acrylic acid polymers prepared by inverse suspension,emulsion polymerization or solution polymerization. Inverse suspensionpolymerization is generally used to prepare polyacrylamide-based SAPsand involves dispersing a monomer solution in a non-solvent, formingfine monomer droplets to which a stabilizer is added. Polymerization isthen initiated by radicals from thermal decomposition of an initiator.

SAPs found to be particularly suitable include, for example, AQUA KEEP®Super Absorbent Polymer manufactured by Sumitomo Seika Chemical Company(Osaka, Japan). For some embodiments, a fast-acting version of AQUAKEEP® found to be suitable is AQUA KEEP® 10SH-P. Additional polymers canbe found commercially as CABLOC 80HS, available from Stockhausen Inc.,Greensboro, N.C.; LIQUIBLOCK® 2G-40, available from EmergingTechnologies, Inc., Greensboro, N.C.; SANWET IM1000F, available fromHoechst Celanese Corporation, Bridgewater, N.J.; AQUALIC CA, availablefrom Nippon Shokubai Co., Ltd., Osaka, Japan; and SUMIKA GEL, availablefrom Sumitomo Kagaku Kabushiki Kaisha, Japan. Additional SAPs are alsocommercially available from a number of manufacturers, such as DowChemical (Midland, Mich.) and Chemdal (Arlington Heights, Ill.). Any ofthe aforementioned SAPs can be included as a blend of two or morepolymers, so long as the majority of the polymer (more than 50% andpreferably more than 70%, weight per weight) has an absorption capacityequal to or greater than 200 gms per gram.

Absorption measurements can be conducted under several methods,including the tea-bag method, centrifuge method and sieve method.According to the tea-bag method, a sample is placed in a bag measuringabout 5×5 cm and the bag is then sealed around its perimeter. The bag isthen placed in a dish with an excess of either water or 0.9% NaClsolution and the sample is allowed to absorb the solution and swellfreely in the bag for one hour or until it reaches equilibrium. The bagis then removed to separate the sample from any excess solution andweighed to calculate the swelling capacity. The absorption capacity ofthe polymer sample can then be calculated in accordance with thefollowing formula:

$A_{s} = \frac{m_{m} - {m_{b}\left( {1 + A_{b}} \right)} - m_{s}}{m_{s}}$

Where: A_(s)=sample absorbency; A_(b)=tea bag material absorbency;m_(m)=weight of tea bag with sample after absorption; m_(b)=weight ofempty, dry tea bag; and m_(s)=weight of dry sample.

In one embodiment, the SAP (or at least a majority of the SAP if a blendof two or more is used) has an absorption capacity of at least 200 g/g,where 1 g of SAP is capable of absorbing up to 200 g of water. The SAPcan also be a fast acting polymer with an absorption rate of no morethan 20 seconds, and more preferably no more than 10 seconds or no morethan 5 seconds.

Encapsulation

All of the disclosed embodiments can be further processed to includesome degree of encapsulation of components to control the exothermicreaction. For example, one approach is to encapsulate the GA particlesor the gel-forming composition to both extend its shelf life and controlthe release of energy once exposed to the activating solution.“Encapsulation,” as used herein, means that at least portions of the GAor other parts of the gel-forming composition are substantially enclosedin a suitable encapsulation material, such that the encapsulationmaterial is adhered to the surface of the particles. “Suitableencapsulation material,” or “encapsulant,” as used herein, means amaterial that is sufficiently robust to withstand formulation andmanufacturing conditions of the gel-forming compositions, is compatiblewith the formulation and does not adversely impact its performance, withthe caveat that extending heat production is not an adverse effect. Inaddition, a suitable encapsulation material adheres to the composition.Adhesion of the encapsulant may occur through covalent chemical bondingor through non-covalent interactions (e.g., ionic, Van der Waals,dipole-dipole, etc.).

“Microencapsulated,” as used herein, means that the average diameter ofthe encapsulated component is from about 1 μm to about 1000 μm. If theencapsulated component is oblong or asymmetrical, then the averagediameter is measured across that part of the component having thegreatest length. In one embodiment, all or some portion of the foregoingcompositions can be microencapsulated, and the encapsulated product hasan average diameter from about 1 μm to about 1000 μm, alternatively fromabout 1 μm to about 120 μm, alternatively from about 1 μm to about 50μm, and alternatively from about 1 μm to about 25 μm. In anotherembodiment, the encapsulated product has an average diameter from about100 μm to about 800 μm, or from about 500 μm to about 700 μm, such as600 μm.

Non-limiting examples of suitable encapsulation materials includepolystyrene, methacrylates, polyamides, nylons, polyureas,polyurethanes, gelatins, polyesters, polycarbonates, modifiedpolystyrenes, and ethylcellulose degradable polymer matrices. In oneembodiment, the encapsulation material is poly(lactide-co-glycolide)(PLG), poly(glycidylmethacrylate)(PGMA), polystyrene, or combinationsthereof. In an alternative embodiment, the encapsulant is hydroxypropylmethylcellulose. Suitable encapsulation materials may have a molecularweight of from about 5 kDa to about to about 250 kDa, alternatively fromabout 200 kDa to about 250 kDa, alternatively from about 50 kDa to about75 kDa, alternatively from about 10 kDa to about 50 kDa andalternatively from about 10 kDa to about 25 kDa.

It should also be understood that it is possible to encapsulate any orall of the alloy components (i.e., both the cathode and anode), eitherthe cathode and/or the anode separately, with or without a binder.Through routine optimization using different combinations of coatings ofvarying components and using known encapsulation techniques, the idealencapsulation format can be determined based on the use to which thecomposition is being put. For example, for a body wrap intended toachieve a therapeutic benefit for a longer period of time, a lessdissolvable coating would be desirable to extend the time period of theheat production. Alternatively, for the administration of a medicament,a more dissolvable coating would be desirable to achieve a highertemperature over a shorter time span.

The chemical properties of the above-described coatings and their use ina variety of fields such as nanotechnology, energetic materials and themedical field is well known and such optimization could be easilyachieved based on this vast body of knowledge.

Binders

The gel-forming composition can also include at least one binder, suchas a polymer or plastic, in addition to the SAP. Exemplary bindersinclude natural resins, synthetic resins, gelatins, rubbers, poly(vinylalcohol)s, hydroxyethyl celluloses, cellulose acetates, celluloseacetate butylates, poly(vinylpyrrolidone)s, casein, starch, poly(acrylicacid)s, poly(methylmethacrylic acid)s, poly(vinyl chloride)s,poly(methacrylic acid)s, styrene-maleic anhydride copolymers,styrene-acrylonitrile copolymers, styrene-butadiene copolymers,poly(vinyl acetal)s (e.g., poly(vinyl formal) and poly(vinyl butyral)),poly(ester)s, poly(urethane)s, phenoxy resins, poly(vinylidenechloride)s, poly(epoxide)s, poly(carbonate)s, poly(vinyl acetate)s,poly(olefin)s, cellulose esters, and poly(amide)s. The binders may addedto the gel-forming composition as a solution or emulsion in water or anorganic solvent and blended together using known methods.

Hydrogen Gas Suppression

As contemplated herein, gas suppression and in particular hydrogen gassuppression, is viewed relative to a similar or identical non-suppressedreaction. In a non-suppressed reaction, gas is freely produced at aknown level, previously known level, or a level that can be calculatedbased on the reactants. Gas suppression as contemplated herein refers toa percentage reduction in gas production and release from the formedexothermic composition (e.g., gel, foam, etc.) relative to anon-suppressed reaction. Experimental data provided herein for anexemplary embodiment demonstrates over 90% gas suppression, thoughhigher levels of gas suppression are contemplated up to and including100% gas suppression. In certain embodiments, a gas suppression ofbetween at or about 30% to at or about 95% is provided. In certainembodiments, a gas suppression of at or about 37%, or over about 37%, isprovided. In certain embodiments, a gas suppression of between about 37%to 93%, at or about 93%, or over about 93%, is provided.

In one embodiment, a gel-forming exothermic composition that suppresseshydrogen gas byproduct can be prepared from a homogenous mixture of SAP,one or more GA particles, and a metal with secondary shell or electronicorbit bonding properties, also referred to as metallic secondary shells.This metallic secondary shell can inhibit or prevent the formation ofhydrogen gas due to reaction with the secondary shell electrons orwithin the electron sharing patterns, eliminating the hydrogen byproductat outermost surfaces of the GA alloy particles. Effectively, themetallic secondary shell thwarts the production of hydrogen gases at thesurface level. Typically, most elements can only use electrons fromtheir outer orbital to bond with other elements. These metals with“secondary-shell” bonding properties can use the two outermostshells/electron orbitals, e.g. the s orbitals, d orbitals, p orbitalsand/or f orbitals common to the electronic structure of these metallicsecondary shells, to bond with other elements to produce unexpectedcombinations. In the case of this embodiment, instead of the hydrogenatom being reduced and becoming H₂ or molecular hydrogen gas, it isinhibited by this secondary interaction as it bonds with the elementalMagnesium atoms, Magnesium Hydroxide, Magnesium Oxide and/or watermolecules.

Exemplary metallic secondary shells can include transitional metals suchas Scandium, Titanium, Vanadium, Chromium, Manganese, Iron, Cobalt,Nickel, Copper, Zinc, Yttrium, Zirconium, Niobium, Molybdenum,Technetium, Ruthenium, Rhodium, Palladium, Silver, Cadmium, Hafnium,Tantalum, Tungsten, Rhenium, Osmium, Iridium, Platinum, Gold, Mercury,Rutherfordium, Dubnium, Seaborgium, Bohrium, Hassium, Meitnerium, andUnunnilium.

One embodiment of the metallic secondary shells can include ManganeseDioxide. Manganese Dioxide is an effective inhibitor for hydrogen gas,is relatively inexpensive, readily available, safe and harmless to theenvironment, people, plant and animal life.

Any of the herein disclosed metallic secondary shells can be combinedwith the GA particles by milling them together with a ball mill, andthen further mixing the Super Absorbent Polymer (SAP) materials togetherwith the composition. In certain embodiments, a homogenous mixture canbe generated using any of a variety of commercially available mixers andblenders, such as drum mixers, braun mixers, ribbon blenders, bladeblenders, V-shaped blenders, batch mixers, or the like. A preferredblender is one that does not excessively shear the GA particles, themetallic secondary shell, or SAP. Depending on the type of equipmentused, the two main components and any optional components are added tothe mixing vessel either sequentially or simultaneously and mixing iscarried out until a uniformly blended product is formed.

With this gel-forming composition, output gasses are drastically reducedand heat is safely and effectively produced, in the absence of oxygenfor activation and largely without a hydrogen gas byproduct. In someembodiments, it has been found that between 90-100% of hydrogen gasbyproduct has been suppressed or inhibited as compared to if thesecondary shell were not included in the gel-forming composition.

In other embodiments of this composition, as a result of the netinhibition of hydrogen gas, other improvements are provided. Forexample, typical Mg—Fe alloy reactions with water produce a very“metallic odor” as the human olfactory sense can detect the hydrogen gasas a metal smell. Typical Mg—Fe alloy reactions with water produce avery “metallic odor,” which the human olfactory senses can discern. Thisodor, while non-toxic, can be very offensive to certain people,especially in the presence of food. The eating experience is both tasteand odor related, so an offensive odor can ruin an eating experience.While food and eating is one example, the benefits of preventing suchmetallic odors provides a number of other benefits and a broader rangeof potential uses of the underlying compositions. Certain embodiments ofthis composition resolve this problem by preventing the metallic odorfrom originating, and by absorbing any other odors into the hydrogelformed by the SAP.

In other embodiments of this composition, to reduce or inhibit the“metallic odor” of the Mg—Fe alloy reaction, activated carbon is usedwith the composition as an odor absorber. While the activated carbon maystruggle, in certain embodiments, to absorb hydrogen gas byproduct,adding activated carbon to the composition unexpectedly interacts withthe “push-pull” or “tug-of-war” between electrons of the exothermicreaction so that the orbital shells and the hydrogen bonding forces workwith and against the SAP gel matrix. In this regard, the SAP's abilityto buffer, control, lengthen and make predictable the heat profiles canbe affected by adding activated carbon. Surprisingly, the addition ofactivated carbon helps make the exothermic reaction more efficient andlonger yield with an overall higher caloric output. The activated carboncan be present in an amount of about 2 to 25% of the composition.

Activated carbon can include a combination of graphite materials, othercarbon powders in various particle sizes. In general, activated carbonforms contemplated herein are electrically conductive forms of activatedcarbon. Using combinations of some or all of these modifiers to theelectrical interactions of the gel-forming composition, is particularlyadvantageous as to overall efficiency of the exothermic reaction.Specifically, as the magnetic qualities of the conductive mineralinteract with the above mention electrical/hydrogen bond strugglebetween the SAP and the alloy.

In other embodiments, an expandable, exothermic composition is disclosedusing Magnetite (Fe₃O₄) in combination with one or more of the galvanicalloy particles and SAP embodiments described in this disclosure. UsingMagnetite is particularly advantageous since when activated with anaqueous solution, an exothermic reaction can be generated having aunique heat curve (e.g., can generate heat a longer duration of timeand/or at higher temperatures) without sacrificing heat output duration.

The activating solution can be generally an aqueous solution, such aswater. It is also important to note that either the gel-formingcomposition or the activating solution contains at least oneelectrolyte, which assists in the electrochemical process that is neededto initiate the exothermic reaction. As used herein, the term“electrolyte” means a substance containing free ions that iselectrically conductive. Electrolyte solutions are usually ionicsolutions and commonly exist as solutions of acids, bases or salts.Salts when placed in an aqueous solvent such as water dissociate intotheir component elements. Examples of preferred electrolytes includepotassium chloride, sodium chloride and calcium chloride.

The particulate gel-forming composition is tested by measuring expansionvolume and rate, as well as heat production and retention. A particulategel-forming composition is considered optimal if it expands(volume/volume) at least two fold, and preferably five fold or even tenfold. It is considered to be “efficient” if it is capable of achieving atemperature of at least 105° F. and maintaining a temperature of atleast 100° F. for one hour.

In one embodiment, magnesium-iron particles can be prepared by mixingtogether 2-20% by weight iron with 80-98% by weight magnesium in ahermetically sealed ball mill.

In one embodiment, the exothermic particulate gel-forming compositionhas an absorption capacity of greater than 400 g/g.

In one embodiment, the blended mixture is formed by mixing a weightratio of 20:1 to 5:1 galvanic alloy particles to super absorbentpolymer. In other embodiments, the mixture is formed by mixing a weightratio of approximately 1:1 galvanic alloy particles to super absorbentpolymer. In other embodiments, the mixture is formed by mixing a weightratio of 20:1 to 5:1 super absorbent polymer to galvanic alloyparticles.

Air is evacuated with an inert dry gas prior to milling. Millingcontinues at or near room temperature (e.g., 15 to 50° C.) until theproduct is uniform. The galvanic alloy product can be tested for itsability to react when contacted with saline solution (e.g., 0.5 to 10%sodium chloride) by measuring a loss in weight, primarily due to theemission of water vapor.

In frequent embodiments contemplated herein, the composition is adaptedto provide for minimal or approximately zero gases to be produced orreleased from the composition (referring to the reacted, reacting,formed, gel/foam, expanding or expanded, exothermic, etc. composition)during or otherwise as a result of the exothermic reaction. Infrequently included embodiments, over at or about 40%, over at or about45%, over at or about 50%, over at or about 55%, over at or about 60%,over at or about 65%, over at or about 70%, over at or about 75%, overat or about 80%, over at or about 85%, over at or about 90%, or over ator about 93%, or over at or about 95% of gases produced by theexothermic reaction are suppressed and not released from the composition(again, referring to the reacted, reacting, formed, gel/foam, expandingor expanded, exothermic, etc. composition) during or otherwise as aresult of the exothermic reaction.

Hydrogen Byproduct Sequestration

In another embodiment, GA particles can be blended or mixed with superabsorbent polymers and a permanganate or ferrate oxidant, such aslithium permanganate, sodium permanganate, potassium permanganate,lithium ferrate, sodium ferrate, or potassium ferrate, to form ahomogenous mixture. In this regard, a safe, self-heating compositionbased on an oxidation reaction of GA particles such as Mg—Fe isdisclosed for oxidizing or eliminating the hydrogen within thecomposition before the hydrogen gas byproduct can escape. Thegel-forming composition can be activated in the absence of air uponcontact with an activator solution, such as an aqueous electrolytesolution such as water or saline solution, as previously described.

Adding a permanganate or ferrate oxidant such as potassium permanganateor potassium ferrate to the GA and SAP mixture results in an oxygensource capable of combining with the hydrogen released by the Mg—Fealloy, before it can convert to hydrogen gas and escape. In turn, duringthe reaction, water and hydrogen peroxide (H₂O₂) can be produced, whichin turn feeds back into supplying the Mg—Fe alloy with a source of waterto aide in its oxidation-reduction reaction. Hydrogen peroxideultimately breaks down in this embodiment into water and another sourceof oxygen molecules. In other words, H₂ gas byproduct can be capturedand converted into water. While potassium permanganate or potassiumferrate may be preferred, other reducible species can be used within theconfines of this disclosure.

In certain embodiments of this composition, using such oxidants with thegel may result in a purple stain or discoloration attributable to, forexample, potassium permanganate. For certain applications, such as withwarming of food, this could be a prohibitive byproduct because the foodcontainer may contacts a permeable pouch and the staining agents wouldtransit out of the permeable pouch onto the food container and thus tothe hands of the person eating the food. However, this discoloration andstaining can be resolved by the gellation of the composition. Forexample, a rubber-like, thick hydrogel that is exhibited in certainembodiments can sequester liquids before they stain or discolor thesurrounding material. The transfer of the discolored solution can thenbe reduced or eliminated since the staining agents are “trapped” orsequestered by the gel. At the same time, the oxygen generated by thesereducible species can flow or “bubble through” the gel allowingrecombination with free hydrogen molecules, which can take place withinthe gel.

The composition and activation by the liquid activator can take placeinside a sealed container to permit time for any staining agent to beabsorbed and sequestered the gel-forming composition. In certainembodiments, one or more layers of the container may optionally bepermeable whereas others may optionally be impermeable.

In certain embodiments, the heat generated within the container expandsthe container due to the production of air and the outflow of watervapor. Accordingly, the container must be vented to outside atmosphericpressure. This venting can occur via a panel of permeable material suchas non-woven (or woven) fabric, a perforated plastic cover, or the like.This permeable layer may be disposed over a chamber where thecomposition comes into contact with the aqueous solution. In order tofurther delay any leakage of the staining solution, a layer ofwater-soluble film or coating may also be applied to the inner side ofthe permeable layer immediately adjacent the composition. A non-limitingexample of water soluble material can be polyvinyl alcohol (PVA orPVOH), but any water-soluble coating or film can be used as needed orrequired. In other embodiments, the container can include asteam-pressure valve. These “valves” can vent steam or hot air pressureat a predetermined level. This level of delay is, in certainembodiments, time-programmed to ensure that all liquid staining agentsare sequestered.

By delaying the venting of steam and heated byproduct gasses from thesealed container, further mixing and combining can occur as to the freeoxygen introduced by the reducible species reference above and the freehydrogen produced by the oxidation of the GA alloys. In turn, hydrogenbyproducts can be further eliminated. Additionally, in certainembodiments, as the heat and wetness of the gel and steam permeate thewater-soluble coating, it may quickly dissolve before substantialpressure can build within the container. In turn, the pressure can bereleased through the permeable layer. This delay can also ensure thatall free hydrogen gas is removed.

An Exothermic Gel With No Hydrogen Gas Byproduct

In another embodiment, a catalyst for peroxide decomposition can beblended or mixed with a buffering agent, such as the aforementioned SAP,to form a mixture such as a powder mixture that is uniform or otherwisehomogenous. When the catalyst is combined with the peroxidedecomposition and the buffering agent, an exothermic reaction can becaused that imparts no hydrogen gas byproduct. Other buffering agentsare contemplated for use with the composition, including particles fromblended compressed sponge, clay particles, and other synthetic andmodified natural materials. Some synthetic superabsorbent materialpolymers contemplated for use with the composition as a buffering agent,including the alkali metal and ammonium salts of poly(acrylic acid) andpoly(methacrylic acid), poly(acrylamides), poly(vinyl ethers), maleicanhydride copolymers with vinyl ethers and alpha-olefins, poly(vinylpyrrolidone), poly(vinylmorpholinone), poly(vinyl alcohol), and mixturesand copolymers thereof. However, the composition is not so limited andother superabsorbent materials contemplated for use with the compositioninclude other natural and modified natural polymers, such as hydrolyzedacrylonitrile-grafted starch, acrylic acid grafted starch, methylcellulose, chitosan, carboxymethyl cellulose, hydroxypropyl cellulose,and certain natural gums, such as alginates, xanthan gum, locust beangum and so forth.

The amount and characteristics of the buffering agent for use with thecatalyst for peroxide decomposition can be selectively varied to controland/or stabilize the exothermic reaction associated with thecomposition. The buffering agent may also be selectively varied toadjust the caloric value output of the composition at a higher or lowerrate by suppressing, for example, a carbonate solution with, forexample, a magnesium sulfate. In turn, this affects the mechanism bywhich the composition reacts so that hydrogen peroxide decomposition iscapable of flattening. This is particularly advantageous as it rendersdecomposition more efficient since it has also been discovered thatrendering a stable exothermic reaction more inefficient or unstable isone approach to control or modifying output of the reaction.

The exothermic, expandable composition in these embodiments can beactivated upon contact with an activator solution containing a peroxide,e.g. hydrogen peroxide (H₂O₂). For example, a peroxide decompositioncatalyst can be blended with SAP and activated with hydrogen peroxide toproduce an exothermic reaction. The peroxide decomposition catalyst canbe any peroxide decomposition catalyst suitable for mixing with SAP orone or more other buffering agents. For example, the peroxidedecomposition catalyst can be manganese oxide, a ferric salt such asferric chloride, or an enzyme such as catalase.

In certain embodiments, encapsulation of the catalyst can affect thecurve of heat output, delay or prolong the reaction, based on solubilityof the encapsulant. Other approaches to affecting the heat output mayinclude varying the catalysts, including manganese oxide (MnO₂), zincoxide (ZnO), copper oxide, PhO₂, lead dioxide, red iron (III) oxide,peroxidase enzymes, potassium iodide, ferric chloride, or the like.

This composition is particularly advantageous as the exothermic reactionassociated with the composition is long-lasting, safe, controlled, andthe activator solution has a much lower freezing point versus salinesolution or water. This is particularly useful in operating environmentswhere temperatures can be substantially reduced such as higher altitudesor sub-zero conditions. Preferably, 35% weight hydrogen peroxide can beused with a freezing point of −31° C., however, other weight percentagescan be used as needed or required. Moreover, because the reaction iscatalytic, the presence of the peroxide decomposition catalyst can beminimized in the SAP mixture or mixture with one or more other bufferingagents. In one preferred embodiment, a homogeneous mixture of manganeseoxide and SAP can be treated with a peroxide solution to generate anexothermic reaction that produces only water and oxygen gas.

The gel-forming compositions of the present disclosure are usefulbecause they form an expanding gel or foam matrix when hydrated, andcreate a balance between energy release and energy governance. Incertain embodiments, this is brought about by the relationship betweenthe SAP and other active ingredients in the herein disclosedcompositions. Though not wishing to be bound by any theory of operation,the SAP absorbs the aqueous solution rapidly, which limits the reactionpotential of the remaining ingredients of the composition. A controlledreaction then ensues as moisture is transferred from the gel componentto the remaining component(s). This reaction liberates heat that istransferred back into the gel that stores the heat rather than lettingit escape into the air in the form of heated gases. This synergisticheat storage and distribution system provides a beneficial effect forcommercial applications such as medical, therapeutic and beautytreatments. Since the gel-forming particles expand as they are hydrated,they can be incorporated into any of a number of different apparatusesand as they swell, they expand where desired, which can be used tocreate an even blanket of exothermic gel, thereby maximizing surfacearea contact and eliminating areas of non-uniform heat. The peroxidedecomposition rate can be modified, for example, by sodium carbonatesolution additions and variations and relatively high concentrations ofmagnesium in salt or ionic form, for example, magnesium sulfate.

In the examples that follow, the conditions such as weight ratios,mixing times, and other data points can easily be optimized for theparticular intended use. For example, in a consumer applications, it isoften desirable to provide a composition that achieves a highertemperature than for a medical product intended to contact the skin.

EXAMPLE 1 MgFe Embodiment With Non-Suppressed Hydrogen Gas

In one embodiment, galvanic alloy materials include 0.5 grams of MgFeand 0.5 grams SA60S. The galvanic alloy and SAP (SA60S) mixture isplaced in the test tube and 5 grams of 3% saline solutions is added. Astopper is positioned that forces gases expelled by the exothermicreaction to pass through the tubing into a completely full water flask.Water is displaced into a beaker. The amount of water displaced by thegas evolution was recorded, with test 1 showing 303.2 grams of waterdisplaced, test 2 showing 305.6 grams of water displaced, test 3 showing298.7 grams of water displaced, test 4 showing 301.2 grams of waterdisplaced, and test 5 showing 304. 6 grams of water displaced.

EXAMPLE 2

A. Non-Milled MnO₂ Composition Mixture, Hydrogen Gas Suppressed

In one embodiment, galvanic alloy particles, SAP, and MnO₂ are preparedby being blended together in a blending apparatus to form a powdermixture. The materials include 0.5 grams of MgFe, 0.5 grams SA60S, and0.5 grams MnO₂. The powder mixture is placed in the test tube and 5grams of 3% saline solutions is added. A stopper is positioned thatforces gases expelled by the exothermic reaction to pass through thetubing into a completely full water flask. Water is displaced into abeaker. The amount of water displaced by the gas generation wasrecorded, with approximately 62.9% gas generated versus non-suppressedExample 1, yielding approximately 37% gas suppression.

B. Milled MnO₂ Composition Mixture, Hydrogen Gas Suppressed

In one embodiment, galvanic alloy particles and SAP are prepared byalloying MgFe with MnO₂ using a high-speed ball mill and combining itwith the SAP (SA60S). The materials include 0.5 grams of MgFe/MnO₂,alloy blended with 0.5 grams SA60S. The MgFe/MnO₂ alloy is blended withthe SAP. The blended MgFe/MnO₂ alloy with SAP is placed in the test tubeand 5 grams of 3% saline solutions is added. A stopper is positionedthat forces gases expelled by the exothermic reaction to pass throughthe tubing into a completely full water flask. Water is displaced into abeaker. The amount of water displaced by the gas generation is recorded.Results show a majority of gas produced by the reaction to besuppressed.

EXAMPLE 3

KMnO₄ Potassium Permanganate Composition Mixture, Hydrogen GasSuppressed

In one embodiment, galvanic alloy particles, SAP, and KMnO₄ are preparedby being blended together in a blending apparatus to form a powdermixture. The galvanic alloy materials include 0.5 grams of MgFe, 0.5grams SA60S, and 0.5 grams KMnO₄. The powder mixture is placed in thetest tube and 5 grams of 3% saline solutions is added. A stopper ispositioned that forces gases expelled by the exothermic reaction to passthrough the tubing into a completely full water flask. Water isdisplaced into a beaker. The amount of water displaced by the gasgeneration was recorded, with approximately 6.8% gas generated versusExample 1, yielding approximately 93.2% gas suppression.

It will be understood that many additional changes in the details,materials, steps and arrangement of parts, which have been hereindescribed and illustrated to explain the nature of the invention, may bemade by those skilled in the art within the principle and scope of theinvention as expressed in the appended claims.

The definitions of the words or elements of the following claims are,therefore, defined in this specification to not only include thecombination of elements which are literally set forth. It is alsocontemplated that an equivalent substitution of two or more elements maybe made for any one of the elements in the claims below or that a singleelement may be substituted for two or more elements in a claim. Althoughelements may be described above as acting in certain combinations andeven initially claimed as such, it is to be expressly understood thatone or more elements from a claimed combination can in some cases beexcised from the combination and that the claimed combination may bedirected to a sub combination or variation of a subcombination(s).

Insubstantial changes from the claimed subject matter as viewed by aperson with ordinary skill in the art, now known or later devised, areexpressly contemplated as being equivalently within the scope of theclaims. Therefore, obvious substitutions now or later known to one withordinary skill in the art are defined to be within the scope of thedefined elements. The claims are thus to be understood to include whatis specifically illustrated and described above, what is conceptuallyequivalent, what can be obviously substituted and also what incorporatesthe essential idea of the embodiments.

What has been described above includes examples of one or moreembodiments. It is, of course, not possible to describe everyconceivable combination of components or methodologies for purposes ofdescribing the aforementioned embodiments, but one of ordinary skill inthe art may recognize that many further combinations and permutations ofvarious embodiments are possible. Accordingly, the described embodimentsare intended to embrace all such alterations, modifications andvariations that fall within the spirit and scope of the appended claims.Furthermore, to the extent that the term “includes” is used in eitherthe detailed description or the claims, such term is intended to beinclusive in a manner similar to the term “comprising” as “comprising”is interpreted when employed as a transitional word in a claim.

What is claimed is:
 1. An expandable, exothermic gel-forming compositioncomprising: first and second metallic galvanic alloy particles; ametallic secondary shell comprised of at least one transitional metal;and a super absorbent polymer; wherein the first and second metallicgalvanic alloy particles, the metallic secondary shell, and the superabsorbent polymer are blended with each other; wherein the gel-formingcomposition expands as the gel-forming composition is hydrated andgenerates an exothermic reaction that produces heat for a predeterminedduration of time when exposed to water and an electrolyte.
 2. (canceled)3. The composition according to claim 1, wherein a powder mixture isformed from first and second metallic galvanic particles that areblended with the super absorbent polymer.
 4. The composition accordingto claim 1, wherein the galvanic metallic alloy particles are blended bya blending apparatus with a super absorbent polymer to form a homogenouspowder mixture.
 5. (canceled)
 6. The composition according to claim 1,wherein the transitional metal of the secondary shell consists ofScandium, Titanium, Vanadium, Chromium, Manganese, Iron, Cobalt, Nickel,Copper, Zinc, Yttrium, Zirconium, Niobium, Molybdenum, Technetium,Ruthenium, Rhodium, Palladium, Silver, Cadmium, Hafnium, Tantalum,Tungsten, Rhenium, Osmium, Iridium, Platinum, Gold, Mercury,Rutherfordium, Dubnium, Seaborgium, Bohrium, Hassium, Meitnerium, orUnunnilium.
 7. The composition according to claim 1, wherein thetransitional metal of the secondary shell is Manganese Dioxide.
 8. Thecomposition according to claim 1, further comprising: activated carbonblended with the galvanic alloy particles, secondary shell, and superabsorbent polymer, wherein the activated carbon is blended or alloyedwith magnetite and the activated carbon comprises between 2 and 25% of atotal weight of the composition, and wherein the activated carbonabsorbs an odor produced by the exothermic reaction duringgel-formation. 9-11. (canceled)
 12. The composition according to claim1, further comprising: an electrolyte comprising sodium chloride orcalcium chloride, wherein the super absorbent polymer comprises anabsorption capacity of at least 200 g/g, and wherein the super absorbentpolymer is operable to absorb water without dissolving by solvation ofwater molecules via hydrogen bonds.
 13. (canceled)
 14. The compositionaccording to claim 1, wherein the first and second galvanic alloyparticles comprise magnesium and iron.
 15. (canceled)
 16. Thecomposition according to claim 14, wherein the super absorbent polymeris sodium polyacrylamide.
 17. The composition according to claim 1,wherein the composition further comprises potassium permanganate orpotassium ferrate. 18-19. (canceled)
 20. The composition according toclaim 1, wherein the galvanic alloy particles are formed from a mixtureof between 2-20% by weight iron and 80-98% by weight magnesium.
 21. Thecomposition according to claim 1, formed by mixing a weight ratio of20:1 to 1:20 galvanic alloy particles to super absorbent polymer. 22-23.(canceled)
 24. The composition according to claim 1, wherein thegalvanic alloy particles are microencapsulated by a polymer.
 25. Thecomposition according to claim 24, wherein the polymer is hydroxypropylmethylcellulose.
 26. The composition according to claim 1, wherein thegalvanic alloy particles are encapsulated by a gel formed by the superabsorbent polymer, and wherein the predetermined duration of time is atleast an hour.
 27. The composition according to claim 1, wherein thegalvanic alloy particles do not include iron.
 28. An expandable,exothermic expandable composition comprising: first and second galvanicalloy particles; a super absorbent polymer; and potassium permanganateor potassium ferrate; wherein the first and second metallic galvanicalloy particles, the potassium permanganate or potassium ferrate, andthe super absorbent polymer are blended with each other; wherein thecomposition expands as the composition is hydrated and generates anexothermic reaction that produces heat for a predetermined duration oftime when exposed only to water and an electrolyte. 29-30. (canceled)31. The composition according to claim 28, wherein water and HydrogenPeroxide (H₂O₂) are byproducts of the exothermic reaction. 32.(canceled)
 33. The composition according to claim 28, wherein thecomposition is disposed in a sealed container comprising a liquidpermeable layer or a steam valve. 34-36. (canceled)
 37. The compositionaccording to claim 28, wherein the first and second galvanic alloyparticles comprise MgFe and MnO₂.
 38. An expandable, exothermiccomposition comprising: manganese dioxide blended with a buffering agentcomprising a super absorbent polymer or a blended mixture of compressedsponge and/or clay particles; and wherein the gel-forming compositionexpands as the gel-forming composition is hydrated and produces heat fora predetermined duration of time when exposed only to an aqueoussolution comprising hydrogen peroxide. 39-40. (canceled)
 41. Thecomposition according to claim 38, wherein the composition expands toform an exothermic gel or stiff foam.
 42. (canceled)
 43. The compositionaccording to claim 40, wherein the composition fluffs up as thecomposition is hydrated. 44-46. (canceled)
 47. The composition accordingto claim 38, wherein the buffering agent is a super absorbent polymer,and wherein the manganese oxide and the super absorbent polymer areblended with each other to form a homogenous mixture. 48-51. (canceled)52. The composition according to claim 1, wherein over at or about 40%,over at or about 45%, over at or about 50%, over at or about 55%, overat or about 60%, over at or about 65%, over at or about 70%, over at orabout 75%, over at or about 80%, over at or about 85%, over at or about90%, or over at or about 95% of hydrogen gases produced by theexothermic reaction are suppressed and not released from the compositionduring the exothermic reaction. 53-60. (canceled)